The present invention relates to brake control systems, and more particularly to an economical brake control system.
A known brake control system for a motor vehicle typically includes a master cylinder for developing a brake fluid pressure in response to brake pedal displacement, stroke simulators adapted to accommodate the brake fluid pressure, wheel cylinders mounted to respective wheels and adapted to develop a braking force, an actuator for feeding the brake fluid pressure to the wheel cylinders, and a controller adapted to enable the actuator to feed a controlled brake fluid pressure to the wheel cylinders, as disclosed in Japanese laid-open patent publication No. 5-39008.
Switch valves are provided to normally prevent fluid communication between the master cylinder and the wheel cylinders and permit fluid communication between the actuator and the wheel cylinders and in the event of a system failure, permit fluid communication between the master cylinder and the wheel cylinders and prevent fluid communication between the actuator and the wheel cylinders. The switch valves are mounted to all of the wheel cylinders. This results in an increase in the production cost of the system.
Two pressure chambers are defined in the master cylinder. Switch valves are also arranged in these two pressure chambers so as to normally permit fluid communication between the stroke simulators and the master cylinder, and in the event of a system failure, prevent fluid communication between the master cylinder and the stroke simulators. The stroke simulators are also arranged in the pressure chambers. This arrangement results in a further increase in the cost of the system.
Accordingly, it is an object of the present invention to provide an inexpensive brake control system.